Flexible winding spool



Aug. 31, 1943. L F Y R ETA'L 2,328,335

FLEXIBLE WINDING SPOOL Filed June 19, 1940 3rmeutor: Louls SFRYER \A/AYNE J.JOKILEHTO (Ittorneg Patented Aug. 31, 1943 UNITED STATES PATENT OFFICE Louis S. iitzi zrim iiifl g leveland,

Ohio, assignors to Industrial Rayon Corporation, Cleveland, Ohio, a corporation of Delaware Application June 10, 1940, Serial No. 339,666

' 8 Claims. (01. 242-121) This invention relates to novel means for supporting thread packages; more particularly, it relates to a new type of flexible winding spool adapted for employment in the production, handling and treating of thread-like articles.

Although the flexible winding spool of the present invention is adapted for use in the manufacture, handling, or storage of any type of thread, it is especially applicable to use the production of multiple filament viscose artificial silk thread. In the course of its manufacture by the 'so-called spool spinning system, such thread is customarily wound upon a rigid, perforate spool upon which it is successively subjected to a series ofwet treatments, after which it is dried. During the liquid-treating and drying operations, a rigid able to the drying operation, in which, by reason.

- of the use of a rigid spool, the thread shrinks unevenly. In atypical case, the layers of the thread package lying. nearest the spool are entirely prevented from shrinking. Th intermediatelayers are caused to shrink in different degrees since to a certain extent they are cushioned by other layers as they are dried. The outermost layers,

which dry first, are for the most part not free to shrink when they are dried. As might be expected, the resulting irregularities manifest themselves in various ways and render the prodsurface which, in actual practice, operates to.

prevent free shrinkage. v Spools have been constructed of narrow sheet. metal strips, of wire fabricated to provide a series of axially extending loops, in the form of so-ca'lled gapped cylinders made of springy metal and the .like, but operations with such spools have not proven successful. Among other things, such flexible spools have been found to sag rather than to flex. I They are prone to be damaged, even with ordinary handling. In a short time, they become unusable as a result of fatigue. For these reasons, they have not displaced the conventional rigid spool, this in spite of the latters numerous disadvantages.

The present application contemplates a novel type of spool which is compressible radially when i subjected to uniform pressure, yet sufllciently rigid to withstand rough treatments In the accompanying drawing, Figure 1 is .an isometric projection of a flexible corrugated spool which embodies the novel features of the present invention. Figure 2 represents a transverse section of the spool shown in Figure 1 obtained by passing a plane perpendicularto the axis of said spool at a point intermediate the ends thereof. Figure 3 is a vertical sectional elevation of the spool as seen from line 3--3 of Figure 2.

The spool comprising the preferred embodiment of the invention is made from a comparatively thin gauge sheet metal in which have been formed a plurality of substantially parallel grooves 5 and ridges 6. The number and depth of corrugations to be employed will depend upon 'the diameter of the finished spool, as well as upon the intended use thereof; for example, if a highlyflexible spool is desired, it is advantageous to form therein a smaller number of grooves andridges, but of greater depth. 0n the other hand, I if too many or too deep grooves are present,

especially where the normal diameter of V the finished spool is small, interference between the grooves may unduly limit the radial compress bility of the spool.

At both ends of each groove 5 and ridge 6 are paratus. All sharp edges or burrs which tend to damage or even break the thread as it is unwound from the spool are thusremoved. In ad-- dition, the possibility of injury to the operator resulting from contact with the edges of such spools is eliminated.

In forming the sheet metahto give rise to a generally tubular member, the edges of the materlal extending parallel to the direction ofsaid grooves 5 and rldgesil ar'e'joined in any convenient manner, as by a soldered, folded or welded butt or lapped connection. A' folded joint, such,

one point upon the periphery of the spool of excess metal which results from the employment.

of certain types of Joints produces harmful effects, especiallywhen the filled spool is rotated at high speed, a in the operation of unwinding the thread therefrom.

Most materials after having been shaped mechanically assume a slightly different shape when subjected to ordinary use for a short period of time. After this change which the material undergoes, the article as a whole assumes a constant shape; that is, it takes a permanent set. By virtue of this fact, certain allowances must necessarily be made in the course 'of manufacture of the spools in order that the resultant shape will conform to the requirements defined by'its use. Such allowances are particularly necessary in the fabrication of corrugated spools.

For instance, it has been discovered that if the spool i mechanically formed out of certain materials exactly to the intended final dimension, it

will, after'one or two usings, reduce in size to such an extent that it cannot thereafter be used. For the reason that wrought aluminum. alloys possess virtually allof the more desirable characteristics, such as workability, lightness, and flexibility without early fatigue, besides being somewhat more resistant to corrosion than most other materials, they are especially adapted to use in the present invention. However, deformation of this kind is particularly marked in wrought aluminum alloys, which must therefore be given especial attention.

In practice, it is desirable to employ a spool which has a constant avg-inch outside diameter. In a typical case, therefore, the spool is formed mechanically to an outside diameter of inches from a wrought aluminum alloy sheet material of .010-inch thickness (Brown & Sharp gauge) specified according to the handbook of the Aluminum .Company of America as alloy.52S-%,H.

. This material has a composition of 2.5% magnesium, 0.25% chromium and 97.25% aluminum I and normal impurities, and a Brinell hardness factor of 74' (500 kg., mm. ball).

Metal rings having an inside diameter of 3% inches are applied to either end of the 5-inch spool so that it remains compressed to an outside diameter of 3% inches. The spool is then placed in a heating chamber and subjected for a period of hours to a. constant temperature 'in excess of 130 F., preferably approximately 150 F. After cooling, the rings are removed, whereupon the spool will be found to have assumed a permanent set with a l /24116151? outside diameter. After use under circumstances involving an indefinite number of ilexings, the spool continues to return to normal at the assumed permanent set. P

Other wrought aluminum alloys have been found to display-properties similar to those of the alloy referred to in the foregoing example, varying principally in the degree of shrinkage which results from the setting operation. Such alloys are, for example, those designated in the handbook ofthe Aluminum Company of America as SIS-T, 53S-T and SIS-T, all of which have approximately the same composition as SZS- /aH. It will be understood that with such alloys the temperature employed in the setting operation may be greater or less than that above indicated, but is advantageously as high as practicable in order that the period of timerequired to size the spool may be reduced as much as possible.

asaaeet A wide variety of other materials may be used in the fabrication of the spool of the present invention; for example, stainless steel, spring steel, sheet iron, sheet aluminum, etc. Obviously, the material employed must possess a certain degree of springiness and yet should'maintain its shape under all sorts of conditions. It must resist not only fatigue but also the corrosive action of reagents employed in the processing of thread. The latter factor is of very greatimportance in the manufacture of artificial silk thread according to a wet process, for instance, the viscose process.

Materials which are readily attacked by corrosive liquids when employed in spin spools may,

however, be treated to prevent decomposition and weakening of the spool structure. Paints and various types of plastic coatings such as hard rubber, Bakelite, Heresite and the like which possess a certain amount of elasticity and resistance to chipping or cracking have been found to retard the corrosive action df'the coagulating bath upon the spools. Accordingly, such a. coating, while often not strictly necessary, may usual- 1y be employed to advantage.

Modifications in the method or the character of the article may readily be made without departing in any way from the spirit of the present invention. Under certain circumstances, it may be found to be advantageous tocombine the operation of setting the spool'with that of heattreating or tempering the material. Moreover, the spool may be formed with hat edges extending longitudinally of the ridges in place of curved surfaces for the purpose of providing greater sur-' face contact for the thread turns. Many other substances than those already indicated such, for example, as Micarta, Bakelite and other synthetic plastics may be employed in the fabrication of the spool.

The method of fabricating the spool of the present invention is not being claimed in this application but represents the subject matter of a divisional application Serial No. 228,730, filed January 29, 1942, by Louis S. Fryer and Wayne J. Jokilehto.

It is intended that the patent shall cover, by suitable expression in the appended claims, whatever features of ,patentable novelty reside in the invention.

What is claimed is:

l. A radially compressible spin spool of generally tubular form comprising a plurality of v axially extending alternately disposed grooves and ridges, each of said ridges being provided at the extremities thereof with a. beveled edge which extends from a point in the crown of the ridge proximate to the end thereof to the corresponding end of the spool.

2. A radially compressible spin spool of generally tubular form comprising a plurality of axially extending alternately disposed grooves and ridges the extremities of each of which are characterized by beveled edges extending from points in the troughs of the grooves and the crowns of the ridges proximate to the ends thereof to the corresponding ends of the spool.

3. A radially compressible spin spool of generally tubular form comprising a plurality of 4. A flexible winding spool of enerally tubular form the thread-bearing periphery of which comprises a plurality of axially extending ridges the extremities of which are characterized by means for resisting lateralwarping of said ridges and, in addition, for facilitating the withdrawal of thread from the spool and, alternately disposed with respect to said ridges, an equal number 01 axially extending grooves. p

5. A flexible winding spool of generally tubular form characterized by its ability to be radially compressed and to; resume its normal shape in spite of innumerable flexings comprising a ,plu-

rality of axially extending grooves and ridges each of said grooves being provided adjacent theends thereof with individual means for strengthening the spool as a "whole against lateral warping. 6. A flexible winding spool of generally tubular form characterized by its ability to be radially compressed "and to resume its normal shape in spite of innumerable flexings comprising a plurality of axially extending grooves and ridges which are provided with individual means disposed adjacent the-ends thereof for strengthening the spool as a whole against lateral warping.

7. A flexible winding spool of generally tubular form according to claim 5 in which the individual strengthening means are formed integrally with said grooves.

8. A flexible winding spool 01 generally tubular form according to claim 6 in which the individual strengthening means are formed integrally with said grooves and ridges.

LOUIS s. FRYER; WAYNE J. 'JOKILEHTO. 

